This invention relates to a battery, and more particularly to a battery of the structure laminated with plural cells adapted for a secondary or fuel battery.
The battery generally has plural cells in which an electrochemical reaction is taken place to generate an electromotive force. These cells are composed of three chambers such as an electrolyte chamber, cathode and anode active material chambers disposed at both sides of the electrolyte chamber, and cathode and anode plates are arranged at the respective boundaries of these chambers. Electromotive voltage and current obtained from these unit cells are much smaller than the values generally required, and in an actual battery such unit cells are laminated in large number and are electrically connected in series or parallel with each other. For example, as disclosed in U.S. Pat. No. 3,188,242, there is proposed a battery laminated with plural unit cells. In such battery terminals for electrically connecting the respective cells are attached to the cells and are connected outside of the frame of the battery by means of welding, soldering or screw clamping, etc. In such battery the resistance of conductors for electrically connecting these cells or an electric loss caused by the contact resistance at the connections of the conductors is however large enough to be unable to ignore. Further, since the connections of the conductors are externally exposed of the frames of the battery in such battery, it has such disadvantage that the volume and accordingly the weight of the entire battery is increased.
In a battery for practical use as much reduction of the volume, weight and further the cost of the battery as possible is at present most important subject. For the purpose of solving such subject, there have been tried several proposals. For example, it has been proposed an electrical connection between the cells of a battery by employing U-shape electrode plates. This proposal has been disclosed as Japanese Pat. application No. 110663/1973 already filed and disclosed in Japan by one of the inventors of this invention. According to this disclosed invention, good electronconductive material plate such as copper is, for example, bent in U-shape to form an electrode holding frame in a manner windows are provided at both sides of U-shape frame. The cathode and anode plates are respectively attached to the respective windows. There is provided partition frames between both sides of the U-shape frame for forming the cathode and anode active material chambers formed adjacent to each other. Then, these frames are accumulated in plural number to form a battery of the structure laminated with plural cells. In such battery the bottom of the U-shape electrode holding frame becomes an electric connection between the respective cells. However, since two chambers are provided between both sides of the U-shape frame in such structure of the electrode plates, the interval between both sides of the U-shape frame cannot be reduced, but the bottom surface of the U-shape frame becomes relatively long. As a result, the electric resistance of the connections between the respective cells cannot remarkably be decreased. In case a large number of such cells are laminated, the battery itself has considerably large internal resistance as the entire battery. In addition, it is difficult to work such U-shape electrode plates, this disclosed invention has such disadvantage that it is difficult to assemble a battery with such U-sahpe frames.